Are these social networks?

Hi to whoever is reading this.
Thing 4
I guess I'm still a bit unfocused about what social networks are, so I'm not sure if these apply.

This url is for the Association of Independent Information Professionals. I have had my own business as a medical librarian for longer than I care to admit. Through this association, I've gotten discounts to online services, referrals to good clients, and lots of interaction through their discussion list. Most of this is not available unless one pays the annual membership fee. Is this association a social network??

http://aiip.org/

first post

Hi All. I just created this blog. I'm not sure how I'll use it but, if you like chamber music, let's hear from you!